The dishwasher is a home appliance for washing dishes by spraying high pressure washing water to the dishes by using spray nozzles. A related art dishwasher is provided with a tub having a washing space therein, a plurality of dish racks in the tub, spray nozzles for spraying washing water to the dish racks, and a sump assembly for holding the washing water and supplying the washing water to the spray nozzles.
Upon putting the dishwasher into operation, clean external washing water is held in the sump assembly, and the sump assembly supplies the washing water to the spray nozzles. Then, the spray nozzles spray high pressure washing water to the dishes on the dish racks in the tub, for washing the dishes.
As described before, the related art dishwasher cleans the dishes by spraying the high pressure washing water to the dishes. However, this is not adequate for removal of sticky food from the dishes, perfectly.